Post driver

ABSTRACT

A manually operated post driver is provided with the usual capped tube to fit over and ram down against the top of a post, such as of tubular, channel, or angle type construction to drive the post into the ground. In addition, a weight system separate from the capped tube is provided. Stiff springs are interposed between the weight system and the capped tube in order to provide a resilient rebound effect to the weight system in order to minimize manual lifting of the weight system during a post driving operation.

United States Patent 1 3,856,092 Mann 1 1 Dec. 24, 1974 POST DRIVERPrimary ExaminerErnest R. Purser Assistant Examiner-William F. Pate, III[76] Inventor Morley Mann 221 Normandy Attorney, Agent, or Firm-O1son,Trexler, Wolters,

Addison, 111. 60101 Bushnell & Fosse, Ltd. [221 Filed: Apr. 10, 1973 t Amanually operated'post driver is provided with the 5 1 933 usual cappedtube to fit over and ram down against 1 Field 91 126 the top of a post,such as of tubular. channel. or angle 3 type construction to drive thepost into the ground. In addition, a weight system separate from thecapped tube is provided. Stiff springs are interposed between [56]References Clted the weight system and the capped tube in order toUNITED STATES PATENTS provide a resilient rebound effect to the weightsystem 874,499 12/1907 Gunn 173/121 in order to minimize manual liftingof the weight sys- 2,983,323 5/1961 Whitney... 173/119 tem during a postdriving operation 3,747,690 7/1973 Deike 173/121 3 Claims, 4 DrawingFigures PATENTEDDEBZMBM TEL POST DRIVER BACKGROUND OF THE INVENTION Itis common practice to drive posts and other like structures into theground. Mechanical drivers, such as steam operated pile drivers arewell-known in the art for driving relatively large elongated bodies intothe ground. However, in the case of relatively small posts, andparticularly for small scale operations, such as posting of trafficsigns, installation of fencing in a residential yard, etc. the size andnumber of posts to be driven do not economically warrant investment inmechanical driving equipment. Manual drivers for such relatively smallposts, which may be of tubular, channel-shaped, angle-shape, or othercross section, are well known in the art, and generally compriseessentially a heavy, capped steel tube. For example, a steel or ironpipe of IV: to 2 inches or more inside diameter may have a cap weldedonto the upper end thereof. In some instances, the upper end of the pipeis externally threaded and a cap is threaded thereon. The pipe is placedover the post to be driven, and is lifted up and then manually broughtdown rapidly so that the inside of the cap hammers against the top endof the post to drive it into the ground.

In such known manual post drivers the total weight or mass that can beprovided is rather limited, and this may make driving difficult infrozen or sun-baked earth. Handles of some sort may be provided on thepipe for aid in lifting the post driver during operation, or forcarrying.

SUMMARY AND OBJECTS OF' THE PRESENT INVENTION In accordance with thepresent invention a post driver is provided which includes a capped tubeto be received over the post or the like to be driven. However, unlikethe conventional manual postdriver this capped tube is not raised up anddown to hammer against the top of the post. Rather, an additional tubeslightly telescopes over the aforementioned tube, and is provided with aweight system. The weight system including the outer tube moves up anddown manually relative to the capped tube. Guide bars are provided foralignment and for limiting the moving apart of the outer tube and thecapped tube.

Reaction members or flanges are provided on the outer tube and on thecapped tube, and in the illustrative example these reaction members orflanges are relatively toward the bottom ends of the respective tubes.The guide members extend between these flanges, and stiff springsencircle the guide members and rest on their lower flange, and areimpinged against by the upper flange as the weight system is manuallylowered at a rapid rate, thereby to provide a hammering force to theflange of the capped tube, which force is translated by the capped tubeto the top of the post to drive the post.

As the flange of the outer tube engages the tops of the springs thesprings are compressed, and provide a rebound effect on the flange oftheouter tube, thereby at least starting to raise the outer tube and the,weight system. Accordingly, the amount of manual eflort re quired toraise the weight system, and particularly the manual effort involved inlifting the weight system, is greatly reduced.

In addition, the shock load imposed on the arm and hand joints of theparty manually operating the post driver are greatly reduced, therebyreducing discomfort to and undue wear and tear on the operator.

Thus, it will be seen that the principal object of the present inventionis to provide a new and improved manually operated post driver.

A further object of the present invention is to provide a manuallyoperated post driver having a spring system which reduces the manualeffort required in driving a post, and at the same time reduces thediscomfort to and wear and tear on the operator.

BRIEF DESCRIPTIONS OF THE DRAWINGS The invention will be best understoodwith reference to the accompanying drawings wherein:

FIG. 1 comprises a perspective view of the post driver constructed inaccordance with the principles of my present invention;

FIG. 2 is a side view thereof;

FIG. 3 is a horizontal cross-section taken substantially along the line3-3 in FIG. 2; and

FIG. 4 is a fragmentary side view on an enlarged scale with parts brokenaway showing the internal construction of the post driver andillustrating the operation thereof.

DETAILED DESCRIPTION Turning now in greater detail to the drawings,there will be seen a post 10 having a T-shaped cross section. Posts ofother shapes, such as tubular, channel-shaped or angle-shaped canequally well be driven. Such post is being driven into the ground 12 bymeans of my In the present illustrative example of the invention, thepost driver 14 includes a tube 16 having a cap 18 at the upper endthereof. The capp 18 preferably is welded to the tube 16, and preferablyis made of hardened tool steel to withstand the hammering against theupper end of the post l0. The capped tube 16 has welded thereto at thelower edge a disc or flange 20 comprising a reaction member.

The post driver also includes a ram 22 having an outer tube 24telescoped with and sliding over the capped tube 16. The outer tube 16terminates substantially above the lower end of the capped tube and haswelded thereto a reaction member 26 comprising a disc or flange spacedparallel to the disc 20, both being horizontally disposed.

At the upper end of the outer tube 24, there is welded a disc-shapedweight base 28. One or more additional weights or masses 30 are mountedon top of the weight base 28 by means of bolts 32 extending through theweight or weights 30 and tapped into the weight base 28.

Three equally arcuately spaced vertical side members perform multiplefunctions as will be brought on hereinafter, and are welded to the discs26 and 28 through supporting gussets 36 at the upper ends and 38 belowthe disc 26.- These vertical side members serve as handles for carryingthe post driver, and also for operating the post driver in a drivingoperation.,The lower ends 40 of the vertical members 34 extend below thedisc 26 and some, distance below the disc 20 thereby serving as feet tosupport the post driver in upright position when the post driver is atrest.,

Three vertical guides 42 in the form of rods or through bolts arethreaded at their lower ends through the disc and have jamb nuts 44threaded on their lower ends thereof to hold the guide rods 42 inupstanding position extending slidingly through aligned bores in thedisc 26. The guide rods 42 extend up nearly to the weight base 28 andhave limiting stop nuts 46 threaded on their upper ends.

Relatively stiff helical springs 48 encircle the guide rods 42 at thelower ends thereof which rest on the reaction member or disc 20 throughthe intermediary of washers 50. Like washers 52 rest on top of thesprings.

A remaining accessory part of the post driver comprises a bolt 54extending up through a bore 56 in the lower disc or thrust member 20 andthreaded into an alignment bore 58 in the upper disc or thrust member 26for supporting the capped tube 16 and thrust member 20 fortransportation. Preferably the bolt 54 extends above the reaction member26 when threaded into place and has a jamb nut thereon. This bolt isused only for holding the parts together during transportation, andtherefore is shown in phantom in the drawings since the drawings showthe post driver in driving operation.

Operation.

Operation of the present post driver is relatively simple. The carryingbolt 54 is removed, and the capped tube 16 is slipped over'the upper endof the post to be driven. This may be done with the post driver lying onthe ground and the post simply slippled into the capped tube.Thereafter, the post and the post driver are tipped up to vertical,operating position. The stiffness of the springs 48 is determined by therequirements of a given job, although a single set of springs isadequate for most driving operations. it may, under some conditions, benecessary to substitute springs for a given job, but this is easilydone. The stiffness of the springs, and the total mass of the weightbase 28 and additional weight or weights 30 is determined by the typeand size of post to be driven, and the hardness of the ground. As willbe appreciated, frozen or sun-baked ground can be quite hard. Stones orrocks in the ground also may impede driving. Under other circumstances,the ground, particularly if wet, may be quite soft, and driving may bequite easy. Depending on the conditions of the ground, and of the totalweight of the ram 22, the post driver may be manually operated by one,two, or three men.

For the first stroke, the uprights 34 of the ram 22 are gripped andlifted manually. The ram then is brought down manually with considerableforce so that the reaction member 26 impinges against the tops of thesprings 48. The springs, in turn, bear impulsively down against thereaction member 20 whereby to act through the capped tube to cause thecap 18 to hammer the post a certain distance into the ground. Thesprings 48 compress during this ramming operation, and subsequentlyrelease the energy stored therein by causing the ram 22 to reboundupwardly, thus greatly reducing the manual strength or force necessaryto lift the ram. The ram again is then brought manually down, as in thefirst stroke, and the rebounding and downward thrusting continues untilthe post is driven to the desired depth.

In order to present clearly a picture of the post driver comprising thepresent invention, without limiting the same, certain dimensions are setforth as illustrative. For example, the total height of one specimen ofmy post driver is on the order of 2 feet. The diameter of the weightbase 28 and of the reaction members 20 and 26 is on the order of 7inches. The bottom of the reaction member 26 is spaced up about 6 inchesfrom the bottom ends 40 of the vertical uprights 34 while the springs 48are on the order of 4%; inches long. The through bolts or guide rods 42are approximately 19 inches long. The total weight of the specimen postdriver may approximate 50 pounds, although this will vary considerablyin accordance with driving conditions.

The capped tube 16 has an internal diameter on the order of 1% inch andan outside diameter on the order of 1% inches.

Although the telescoping members 16 and 24 conveniently and preferablyare tubular in nature, this particular shape is not necessary, forexample, they could be replaced by channel or angle members. Thespecific example of the invention as herein shown and described is forillustrative purposes only, and various changes will no doubt occur tothose skilled in the art, and will be understood as comprising part ofthe present invention insofar as they fall within the spirit and scopeof the appended claims.

The invention is claimed as follows:

ll. A manually operable driver for the post or the like comprising afirst, inner tube having a cap at the upper end thereof and adaptedtooverlie a post or the like to be driven with the cap impinging againstthe top of said post or'the like, a reaction disc fixed to said tubeadjacent the lower end transversely thereof, a ram having a second tubetelescoping over said first tube and adapted to slide longitudinallyrelative thereto, said ram having a substantial mass including atransverse weight base adjacent the upper end thereof and further havinga reaction disc secured to the ram tube adjacent the lower end andextending transversely thereof, guide rods extending from one of saidreaction discs through the other thereof in sliding relation relative tothe other thereof, and a plurality of compression springs respectivelyencircling said guide rods between said reaction discs and in lostmotion connection with said reaction discs, whereby downward movement ofsaid ram imposes a driving load on said first tubeand said springsthereafter providing an upward restoring force of said ram.

2. A driver as set forth in claim 1 and further including a plurality ofsubstantially vertical side members connected to the ram reaction discand to the weight base and extending downwardly therefrom providingsupporting feet with said driver in upright position, said side memberproviding hand grips for an operator of said driver.

3. A manually operable driver for a post or the like comprising a first,inner tube having a cap at the upper end thereof and adapted to overliea post or the like to be driven with the cap impinging against the topof said post or the like, a disc fixed to said tube adjacent the lowerend transversely thereof, a ram having a second tube telescoping oversaid first tube and adapted to slide longitudinally relative thereto,said ram having a substantial mass including a transverse weight baseadjacent the upper end thereof and further having a disc ram disc and tothe weight base and extending down wardly therefrom providing supportingfeet with said driver in upright position, said side members providinghand grips for an operator of said driver.

1. A manually operable driver for the post or the like comprising afirst, inner tube having a cap at the upper end thereof and adapted tooverlie a post or the like to be driven with the cap impinging againstthe top of said post or the like, a reaction disc fixed to said tubeadjacent the lower end transversely thereof, a ram having a second tubetelescoping over said first tube and adapted to slide longitudinallyrelative thereto, said ram having a substantial mass including atransverse weight base adjacent the upper end thereof and further havinga reaction disc secured to the ram tube adjacent the lower end andextending transversely thereof, guide rods extending from one of saidreaction discs through the other thereof in sliding relation relative tothe other thereof, and a plurality of compression springs respectivelyencircling said guide rods between said reaction discs and in lostmotion connection with said reaction discs, whereby downward movement ofsaid ram imposes a driving load on said first tube and said springsthereafter providing an upward restoring force of said ram.
 2. A driveras set forth in claim 1 and further including a plurality ofsubstantially vertical side members connected to the ram reaction discand to the weight base and extending downwardly therefrom providingsupporting feet with said driver in upright position, said side memberproviding hand grips for an operator of said driver.
 3. A manuallyoperable driver for a post or the like comprising a first, inner tubehaving a cap at the upper end thereof and adapted to overlie a post orthe like to be driven with the cap impinging against the top of saidpost or the like, a disc fixed to said tube adjacent the lower endtransversely thereof, a ram having a second tube telescoping over saidfirst tube and adapted to slide longitudinally relative thereto, saidram having a substantial mass including a transverse weight baseadjacent the upper end thereof and further having a disc secured to theram tube adjacent the lower end and extending transversely thereof,guide rods extending from one of said discs through the other thereof insliding relation relative to the other thereof, and a plurality ofsubstantially vertical side members connected to the ram disc and to theweight base and extending downwardly therefrom providing supporting feetwith said driver in upright position, said side members providing handgrips for an operator of said driver.